At 10-7-5, with 35 points through week 22, Atlanta United is having a banner inaugural season in Major League Soccer. The expansion team is 4-0-2 in its last six games and would make the Eastern Conference playoffs as the sixth seed if the season ended today. Their goal differential of +13 ranks third in all of MLS, and they are ranked ninth league-wide in the Supporters’ Shield standings. Assuming this level of play continues through their final dozen games, Atlanta United is poised to have the best ever opening season by a true expansion team across North American professional sports leagues.

Dating back to MLB’s 1961 addition of the Angels and (now) Rangers, ushering in that league’s expansion era, not a single true expansion team in MLB, the NFL, the NBA, or the NHL has posted a winning record in its first full season. The closest any teams have come to .500 or better are the Carolina Panthers, who posted a very respectable 7-9 record in their first NFL season, and, coincidentally, the NHL’s Florida Panthers who nearly broke even at 33-34-17 in their maiden 1993-94 campaign.

Not only would posting a winning record set a new gold standard for the regular season, Atlanta United is sitting at an 89% probability to make the MLS playoffs according to FiveThiryEight Club Soccer Predictions. Taking the pitch in the postseason would set a challenging precedent for all future expansion franchises – not to mention future United teams. None of the 37 teams in this review played beyond the regular season in their first year of competition, and only three teams made it to the postseason in year two: the 1996 Panthers and Jaguars of the NFL and the Diamondbacks played October baseball in 1999. The range was 2-19 years to break that postseason barrier for the teams in the study. Playoff rounds were added as the leagues grew, and in the NBA and NHL more than half the field traditionally play in the postseason. The mean is 7.35 years to make an initial appearance, and the mode is 5 years (seven teams).

With expanded playoffs in all sports, making the postseason, doesn’t necessarily translate to playing for championships. Of the 37 true expansion teams added to the big four leagues in the modern era, 24 have played in the last game of the season and only 13 have won a title. Three teams have run the table, hoisting the championship trophy in their first postseason appearance: the 1969 (Miracle) Mets, the 1997 Marlins, and the 2000 Ravens. Atlanta United probably wouldn’t mind following the Mets’ and Marlins’ lead by notching their first winning record, first postseason appearance, and first league championship in the same season.
As of this writing, Atlanta United have 12 regular season games left to play, eight at home. They have a 6-2-1 record at home so far this season at Bobby Dodd Stadium. The remaining home games will be in the brand-new Mercedes Benz Stadium, a venue, if proves as advantageous as the temporary home, will ensure the most successful debut season of an expansion team in North American modern professional league history.

Expansion Teams' Performance Data: NFL, NBA, MLB, NHL

[*Current Name

^ Note that when the NBA awarded Charlotte an expansion franchise in 2004, it also awarded it the old Bobcats/Hornets records from 1998-2002 when the original Charlotte franchise moved to New Orleans, thus effectively making the Pelicans the “expansion” team retroactive to 2002, with records only dating back to the 02-03 season. That is not fair for this comparison because it is the Charlotte team roster that was created from scratch and went 18-64 in 2004-5, while the veteran New Orleans team posted a 47-35 record in 2002, the year it was deemed an expansion team on paper. This chart expresses data the opposite of how official NBA stats would present it.

# 1981 was a strike shortened season and MLB modified postseason qualification such that a first-half champion and second-half champion in each division (east/west, AL/NL) played a five-game series to advance to the LCS, doubling the number of playoff teams to 8 for one season only.]

Background on Expansion Teams:

The teams in this comparison had to build their inaugural season rosters from scratch, as opposed to coming from another league with personnel who had already been playing competitively together at a relatively high level. Each professional league has their own restrictions for how expansion teams sign players to their rosters, be it through the amateur draft, an “expansion draft” whereby the new team is allowed to select players from a list of players from the other teams in the league not otherwise protected by those teams according league regulations, and of course free agency.

In the NFL, there are only two franchises, the Chicago Bears and the Arizona Cardinals, which are founding members of original league formed in 1920, the American Professional Football Association. Since there was a significant amount of instability with relocations and mergers during the early years, it makes sense for this exercise to consider expansion teams joining the league after the 1970 merger of the NFL and AFL: Seahawks (1976), Buccaneers (1976), Panthers (1995), Jaguars (1995), Ravens (1996), Texans (2002).

Similarly, with the NBA, there was a lot of expansion and contraction with the league consisting of anywhere from 8-18 teams from 1946-76. In 1976, the NBA treated the addition of four teams formerly with the ABA as expansion teams rather than a merger, however this significantly stabilized the league, which has grown to 30 teams. Teams added since 1980 will be considered: Mavericks (1980), Heat (1988), Hornets^ (1988 NO), Timberwolves (1989), Magic (1989), Grizzlies (1995), Raptors (1995), and Hornets^ (2004 NC).

MLB has arguably the cleanest line of demarcation for expansion in 1961 when the then Washington Senators (Texas Rangers) and Los Angeles Angels were the first additions to the league since the turn of the century. Also in this comparison: Astros (1962), Mets (1962), Royals (1969), Nationals (1969), Padres (1969), Brewers (1969), Mariners (1977), Blue Jays (1977), Rockies (1993), Marlins (1993), Diamondbacks (1998), and Rays (1998).

The NHL will play with 31 teams in 2017-18 when the Las Vegas Golden Knights take the ice, the first new team in the league since Y2K. Between 1967, when the league had doubled from the “original six” to 12 teams, and 1979, when the NHL settled in at 21 teams, there were 10 additions, one contraction, and a lot of relocations. In 1991, the modern era of expansion began, with the teams considered here: Sharks (1991), Senators (1992), Lightning (1992), Ducks (1993), Panthers (1993), Predators (1998), Jets (1999), Blue Jackets (2000), and Wild (2000).